The present invention relates to a magnetic disk apparatus, more specifically to a method of electrically connecting a magnetic head, a magnetic head assembly and a magnetic disk apparatus.
As an information age comes, a magnetic disk apparatus becomes essential to a computer or a word-processor. With increase of an amount of information, the magnetic disk apparatus has been requested to have more storage capacity, higher performance and a reduced size. The magnetic disk apparatus is normally composed of a magnetic disk part and a magnetic head part. As the magnetic disk apparatus keeps higher performance and a smaller size, the magnetic head part has been requested to be more accurate and smaller.
The conventional example of the magnetic head assembly used in the magnetic head part will be described with reference to FIGS. 16 and 17. FIG. 16 is a view showing an outer appearance of the conventional magnetic head assembly. FIG. 17 is an expanded view showing the part around the magnetic head contained in the magnetic head assembly.
A magnetic head 51 of the magnetic head assembly used in the magnetic disk apparatus is composed of a core slider made of ceramics, for example, and a magnetic head element. The magnetic head 51 is fixed on a tabular supporting spring 53.
A lead wire 55 is connected between the magnetic head element 59 provided in the magnetic head 51 and an electric circuit (not shown). The lead wire 55 is coated by an insulating material such as a resin in a manner to keep it insulated from the metallic supporting spring 53. The lead wire 55 is then passed through a protective tube 56, like a vinyl tube and the protective tube 56 is fixed at the supporting spring 53. The fixing of the protective tube 56 having the lead wire 55 therein is done by mechanical (caulking, for example) means. The lead wire 55 located between the magnetic head element 59 and the protective tube 56 is just coated by an insulating material such as a resin without being protected by the protective tube 56.
In the above structure, the portion of the lead wire 55 from the magnetic head element 59 to the protective tube 56 is formed to have a predetermined form for reducing the force given by the lead wire 55 against the magnetic head 51 (in other words, minimizing the adverse effect of the lead wire 55 on the magnetic head assembly when the magnetic disk is rotating at fast speed) in order to keep the posture of the magnetic head element 59 against the magnetic disk stable.
As the magnetic disk apparatus becomes smaller in-size and higher in performance, the magnetic head part has been requested to be smaller and more accurate. As such, it is important to keep the lead wire from the magnetic head element as vertically close to the supporting spring as possible, that is, to reduce the vertical mounting space of the lead wire as much as possible. Conventionally, the portion of the lead wire 55 from the magnetic head element 59 to the protective tube 56 fixed at the tip of the supporting spring 53 is formed to have a predetermined form. This forming of the lead wire 55, therefore, needs horizontal as well as vertical mounting space. This is an impedance to reducing the apparatus in size.
The elasticity of this lead wire 55 has an effect of applying excessive force to the magnetic head assembly when it is used. This results in disadvantageously changing the form of the spring and thereby keeping the position of the magnetic head assembly unstable when it is used.
In fixing the supporting spring 53 on the magnetic head 51, distortion is caused by hardening or shrinking the bonding agent. The distortion directly gives an adverse effect on the supporting spring 53 and the magnetic head 51. That is, the distortion causes as tension against the supporting spring 53 and the magnetic head 51 in a manner to keep them warped. The warpage is a factor in displacing the relative position between the magnetic head element 59 and the magnetic disk.